Currently, audiovisual apparatuses (AV apparatus), which can obtain various contents via various media, have been developed. Examples of the contents are images (still images and moving images), music, web pages, and application programs. One example of the AV apparatuses is an HDD-installed DVD recorder (hard disk drive installed digital versatile disk recorder).
Such an AV apparatus has to have a function to allow users to select one of the contents stored in recording media including the HDD and the DVD, and the broadcast contents. Conventionally, a menu-interaction type GUI (graphical user interface) realizes the function by displaying alternatives of the contents as a list on the screen and receiving a selection from the list, from which a user can perform selection for playback, execution, or recording.
For example, the HDD-installed DVD recorder disclosed by non-patent reference 1 (see below) performs as follows. When the HDD-installed DVD recorder receives a user instruction for a contents selection screen display, displays, names and thumbnails of the contents stored either in an HDD or a DVD, in the form of a list. The list is divided into pages so that one page contains a predetermined number of alternatives arranged in a predetermined order (e.g. descending order of stored dates, or according to channels).
In addition, conventional operation members used in the GUI are a mouse, a ten key, and a jog dial. However, the information inputting apparatus displayed by the following patent reference 1 may also be used.    (Non-Patent Reference 1)    Internet reference    URL:http://panasonic.jp/dvd/recorder/e200h/spec/01.html    (Patent reference 1)    Japanese laid-open patent application No. 2001-184158
Such AV apparatuses as described above can select a desired content from among enormous amounts of contents recorded in an HDD, a DVD, and the like, for playback or for execution at any time. However, the GUI operation for the selection is expected to be troublesome.
For example, suppose using a conventional AV apparatus that can display a list of eight alternatives in a page. When an alternative indicating a desired content exists at page 50, the user has to reach the page 50 by repeating a page-turning operation directed to the operation member many times.
In addition, when the AV apparatus can display the selectable contents as a list by thumbnails, it takes time to process for displaying the list. Accordingly, there will be a lag between the user's instruction operation for turning pages and an actual list display switch. As a result, the user would feel stress because he cannot select the desired contents easily because the list display switch is not displayed smoothly.
If all the selectable alternatives can be displayed as a list at once, it is no longer necessary to turn pages. However, if there are thousands of the selectable alternatives, it takes a great amount of time to generate the list, and the user has to operate the operation members many times to reach a desired alternative in the list. This might worsen the operability even compared to the conventional case.
In view of the above, the present invention has an object of providing a user interface apparatus with improved operability in selection of a desired content from among many alternatives compared to conventional cases, and of providing various technologies relating to such a user interface apparatus.